Standard Endoscopic Mucosal Resection vs Precutting Endoscopic Mucosal Resection Using Novel Disk-Tip Snare for Colorectal Lesions.

Introduction: SOUTEN (KANEKA Co., Tokyo, Japan) is a unique snare with a disk tip. We analyzed the efficacy of precutting endoscopic mucosal resection with SOUTEN (PEMR-S) for colorectal lesions.

Methods: We retrospectively reviewed 57 lesions of 10-30 mm treated with PEMR-S at our institution from 2017 to 2022. The indications were lesions that were difficult for standard EMR due to size, morphology, and poor elevation by injection. Various therapeutic results of PEMR-S such as en bloc resection, procedure time, and perioperative hemorrhage were analyzed, and the results of 20 lesions of 20-30 mm with PEMR-S were compared to those of lesions with standard EMR (2012-2014) using propensity score matching. Additionally, the stability of the SOUTEN disk tip was analyzed in a laboratory experiment.

Results: The polyp size was 16.5 ± 4.2 mm and the non-polypoid morphology rate was 80.7%. Histopathological diagnosis included 10 sessile-serrated lesions, 43 low-grade and high-grade dysplasias, and 4 T1 cancers. After matching, the en bloc resection and histopathological complete resection rates of lesions of 20-30 mm between PEMR-S and standard EMR (90.0% vs. 58.1%, p = 0.03 and 70.0% vs. 45.0%, p = 0.11). The procedure time (min) was 14.8 ± 9.7 and 9.7 ± 8.3 (p < 0.01). The en bloc resection (%) and procedure time of expert/non-expert were 89.7/85.7 (p = 0.96) and 6.1 ± 2.2/18.5 ± 7.2 (p < 0.01). The perioperative bleeding and hemostasis success rates with SOUTEN were 43.9% and 96.0%. In the experiment, the SOUTEN disk tip was fixed stably compared to other EMR snares.

Conclusions: PEMR-S achieved high en bloc resection of colorectal lesions of 20-30 mm though it leaded to long procedure time.